Effectiveness of different types of footwear insoles for the diabetic neuropathic foot: a follow-up study.

OBJECTIVE To compare the effectiveness of different types of footwear insoles in the diabetic neuropathic foot. RESEARCH DESIGN AND METHODS A sample of 241 consecutive diabetic patients (158 men and 83 women, age 57.5 +/- 9.6 years [mean +/- SD], and mean duration of diabetes 12.3 +/- 7.2 years) attending the foot clinic with previous foot ulceration and those considered at high risk of foot ulceration were included in the study. The study groups consisted of group 1, patients provided with sandals with insoles made with microcellular rubber (n = 100); group 2, with sandals with polyurethane foam (n = 59); group 3, with molded insoles (n = 32); and group 4, with their own footwear containing leather board insoles (n = 50). Neuropathy status was assessed using a biothesiometer. Plantar pressure was measured using the RS Scan inshoe pressure measurement system. Data obtained from the metatarsal heads were used as the peak pressure. The state of the sandals was assessed after 9 months. The patients were considered to have had an ulcer relapse when either a new ulcer appeared at the site of a previous one or a new foot ulcer appeared in a different area. RESULTS Patients who were using therapeutic footwear showed lower foot pressure (group 1, 6.9 +/- 3.6; group 2, 6.2 +/- 3.9; and group 3, 6.8 +/- 6.1 kPa; P = 0.0001), while those who used the nontherapeutic footwear showed an increased foot pressure (group 4, 40.7 +/- 20.5 kPa; P = 0.008). The occurrence of new lesions was significantly higher in patients in group 4 (33%) when compared with that of all other groups (4%). CONCLUSION Therapeutic footwear is useful to reduce new ulceration and consequently the amputation rate in the diabetic population.